Artificial aging behavior of SiC_P/AA2009 composite by electric heating: Mechanisms and modelling

SiC_P/Al composite is regarded as a superior alternative material in the aerospace industry due to its excellent properties. Meanwhile, electrically-assisted aging (EAA) heat treatment has emerged as a promising method for artificial aging to obtain better aging performances. This study explores the potential of EAA heat treatment to enhance the aging kinetics of SiC_P/Al composite. The impact of EAA on the aging behavior of SiC_P/AA2009 composites is investigated and compared with conventional furnace aging treatment, ranging from microstructure to macroscopic properties. The electric current has few effects on the evolution trend of aging strength, but can enhance the aging process of SiC_P/AA2009 with higher yield strength (about 13.7 MPa improvement) and ultimate tensile strength (about 9.7 MPa improvement). Analysis of microstructures demonstrates that EAA can generate more nucleation sites and reduce consumption of Cu atoms by Cu–Mg co-clusters near SiC_P interface, resulting in more θ’ phases compared to conventional aging (CA). Additionally, more fine precipitates and dislocations contribute to higher strength under EAA condition. Subsequently, a precipitation kinetic model based on the Lagrange-like approach is employed to predict the particular electric current effects on the particle size distribution and evolution during aging, and to calculate yield strength by establishing a relationship between microstructural characteristics and macroscopic performance, providing a model basis for the design of potential EAA processes.